A method for the identification of time delays in linear systems

An automatic method is presented for the identification of time delays and parameters in linear systems. It is assumed that processes to be identified can be described by linear differential-difference equations. Unknown parameters in these equations are determined by a continuous steepest descent minimization of an error function. If the process parameters are constant, a region exists in the parameter space in which the tracking paramters converge to the process parameters. If all process time delays are known as well, the tracking parameters will always converge. Two examples are presented which show that the method may be used to identify slowly varying parameters. A third example indicates techniques leading to a more economical implementation of the method.